Khloé Kardashian's estranged husband had an unspecified procedure done at Cedars-Sinai Medical Center, and is said to be connected to his bout with pneumonia, according to People magazine.

"Lamar is in a very fragile state," a source tells the publication. "The infection, that is being aggressively treated with strong intravenous antibiotics, is unfortunately not getting better. There are many concerns about his health."

The Keeping Up With The Kardashians star is reportedly the only visitor allowed by his bedside until he improves, according to E! News.

Television personality Khloe Kardashian (L) and Lamar Odom in 2010

Khloé has been by the athlete's side since he was hospitalised in Las Vegas on 13 October (15), when he was found unconscious at the Love South Brothel in nearby Crystal, Nevada. He woke up from his coma a few days later, and on Monday (19Oct15), he was airlifted to Cedars-Sinai, where he has been ever since.

On Wednesday (21Oct15), the pair reportedly signed a petition requesting a judge to dismiss divorce papers that had yet to be finalised by a judge. The request was granted and reports suggest their divorce case is now over.

Meanwhile, in new court documents obtained by The Wrap, a detective with the Nye County Sheriff's Office says two brothel prostitutes claim Lamar had taken "an unknown substance in the form of an unidentified pill", and that he "possibly ingested cocaine in the bathroom adjoining to the bedroom" where he was staying.

"They indicated that they heard him snorting," the detective states in the papers. "They indicated that they had vague knowledge of him using illicit drugs... I believe that Mr. Odom may be - or may have been under the influence of a controlled substance."

The detective added Lamar was found with "a white substance coming from his mouth as well as bleeding from his nose", which are "signs or evidence of a drug overdose."

Results of a toxicology test taken by Lamar on 14 October (15) have yet to be revealed.